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DWI Alcohol New Hampshire

DWI Alcohol (Driving while intoxicated)


To obtain a DWI alcohol conviction, the prosecutor must prove beyond a reasonable doubt that your ability to operate a motor vehicle was impaired due to alcohol. Under the influence is defined as: impairment to any degree.

The police officer’s training in DWI detection is usually based upon standards set forth by the National Highway Traffic and Safety Administration (NHTSA). It is imperative that the person who represents you on your DWI is intimately familiar with this manual and the Field Sobriety Tests. Attorney Hynes is not only certified to administer Field Sobriety Tests, he is certified as an instructor to teach others how to administer the tests.


Alcohol Information

There are a few types of Alcohol. Methanol (Methyl alcohol / wood alcohol), Ethanol (ethyl alcohol / grain alcohol / Alcohol fit for human consumption), Propanol (Isopropyl alcohol / rubbing alcohol), Butanol (Butyl alcohol), and Ethanediol (Ethylene glycol / antifreeze). For purposes of this book, and for DWI, we will be referring to Ethyl alcohol.

Alcohol itself has no odor/ a faint odor. What the officer is actually smelling (or claims to be smelling) is the additives/congeners. Alcohol is categorized in the depressant class of drugs. To affect the brain, and in turn the body, alcohol must be absorbed into the blood stream and circulated throughout the body.

Typically, most beers are around 5% alcohol, wine around 10-20%, and distilled spirits 40-50%. A rough rule of thumb is that one 12 oz. glass of beer, one half glass of wine, and one shot of vodka/distilled spirit, will all be around the same alcohol content, commonly referred to as one drink.



Alcohol must be absorbed into the body, distributed to the brain, and is then eliminated over time. Many things affect how quickly alcohol will absorb, including your gender, when you last ate/ what you ate, age, what type of alcohol you consumed, your weight, if you smoked any cigarettes, and if you consumed any drugs.

Alcohol gets absorbed differently from person to person. A rough estimate is each drink equals around .015 BAC and takes about an hour to absorb. Again, everyone is different. Ranges of 15 minutes to 6 hours have been reported. This is important because if you drank right before driving, the alcohol would not yet have been in your system.



The rate at which alcohol leaves the body is referred to as an elimination rate. It is different for everyone and even changes in the same person. The average elimination rate is .015 -.020 per hour

Many things that affect the elimination rate are the same things that affect absorption rates. They include gender, amount/ type of alcohol ingested, and any food ingested.


Phase I Vehicle in Motion (Car moving)

The first part, or phase, of DWI detection is a vehicle in motion. During this phase, the officer is to observe the driving, to look for certain signs of impairment.

The officer is/ should be looking for the following cues:


Cues while Driving

Problems Maintaining Proper Lane Position:

Weaving, weaving across lane lines, straddling a lane line, swerving, turning with wide radius, drifting, and almost striking an object or vehicle


Speed and braking problems:

Stopping problems, Accelerating or decelerating rapidly,

Varying speed, Slow Speed (10 mph + Under limit)

Speeding, in itself, is not a sign of impairment. It takes greater coordination/mental & physical faculties to control a vehicle that is traveling faster. Some officers believe speeding is a sign of impairment. In my view, they are incorrect.


Vigilance problems:

Driving in opposing lanes or wrong way on one-way street, Slow response to traffic signals, Slow or failure to respond to officer's signals, Stopping in lane for no apparent reason, Driving without headlights at night, Failure to signal or signal inconsistent with action.


Judgment problems:

Following too closely, Improper or unsafe lane change, Illegal or improper turn (too fast, jerky, sharp, etc.), Driving on other than designated roadway, Stopping inappropriately in response to officer, Inappropriate or unusual behavior (throwing objects, arguing, etc.)

Appearing to be impaired - eye fixation, tightly gripping the steering wheel, slouching in the seat, gesturing erratically or obscenely, face close to windshield, driver's head protruding from vehicle.


Post Stop Cues

Difficulty with motor vehicle controls, Difficulty exiting the vehicle, Fumbling with driver’s license or registration, Repeating questions or comments, Swaying, unsteady, or balance problems, Leaning on the vehicle or other object, Slurred speech, Slow to respond to officer/officer must repeat, Provides incorrect information, changes answers, Odor of alcoholic beverage from the driver


The Stopping Sequence:

An attempt to flee, No response, Slow response, An abrupt swerve, Sudden stop, Striking the curb or another object.


Special Cues for Motorcyclists

There are separate cues for motorcycles.

Drifting during turn or curve, Trouble with dismount, Trouble with balance at a stop, Turning problems (e.g., unsteady, sudden corrections, late braking, improper lean angle), Inattentive to surroundings, Inappropriate or unusual behavior (e.g., carrying or dropping object, urinating at roadside, disorderly conduct, etc.), Weaving, Erratic movements while going straight, Operating without lights at night, Recklessness, Following too closely, Running stop light or sign, Evasion, Wrong way


Phase II - Personal Contact (When the cop interacts with you)


Bloodshot eyes, Soiled clothing, Fumbling fingers, Alcohol containers, Drugs or drug paraphernalia, Bruises, bumps, or scratches, Unusual actions



Slurred speech, Admission of drinking, Inconsistent responses, Abusive Language, Unusual statements



Alcoholic beverages, Marijuana, Cover up odors like breath sprays, Unusual odor


Phase III – Standardized Field Sobriety Tests

It is important to note these are "standardized" tests. The officer cannot/should not deviate from the training or scoring. The manual emphasizes this in capital letters and in bold:







Again, knowing how the tests are supposed to be administered is necessary to be able to best defend a DWI charge.


Horizontal Gaze Nystagmus (Eye Test)

The first test is the Horizontal Gaze Nystagmus test (Pen/ Eye test). A nystagmus is an involuntary jerking of the eye. The officer, when moving a stimulus (pen, finger) across your face, is looking to see if the eye "jerks" instead of moving smoothly.

It is impossible for you to know if you passed this test. The part you have to do correctly is keep your head still and follow the pen with just your eyes. However, this is not what the officer is scoring you on.


One of the main problems with this test is THINGS OTHER THAN ALCOHOL CAUSE A NYSTAGMUS. One Court has specifically listed 38 different possible causes of nystagmus other than alcohol:

“(1) problems with the inner ear labyrinth; (2) irrigating the ears with warm or cold water under peculiar weather conditions; (3) influenza; (4) streptococcus infection; (5) vertigo; (6) measles; (7) syphilis; (8) arteriosclerosis; (9) muscular dystrophy; (10) multiple sclerosis; (11) Korchaff's syndrome; (12) brain hemorrhage; (13) epilepsy; (14) hypertension; (15) motion sickness; (16) sunstroke; (17) eye strain; (18) eye muscle fatigue; (19) glaucoma; (20) changes in atmospheric pressure; (21) consumption of excessive amounts of caffeine; (22) excessive exposure to nicotine; (23) aspirin; (24) circadian rhythms; (25) acute trauma to the head; (26) chronic trauma to the head; (27) some prescription drugs, tranquilizers, pain medications, anticonvulsants; (28) barbiturates; (29) disorders of the vestibular apparatus and brain stem; (30) cerebellum dysfunction; (31) heredity; (32) diet; (33) toxins; (34) exposure to solvents, PCBS, dry cleaning fumes, carbon monoxide; (34) extreme chilling; (35) eye muscle imbalance; (36) lesions; (37) continuous movement of the visual field past the eyes, i.e., looking from a moving train; (38) antihistamine use.[1]

Further, some people have a natural nystagmus.


Administering the Horizontal Gaze Nystagmus test (HGN)

To administer the test correctly, the officer must do the following:



Preliminary qualifications -The entire test is administered by holding a stimulus (pen, finger) approximately 12-15 inches away from your nose slightly above eye level. The officer checks for equal tracking, equal pupil size, and resting nystagmus.


Three Steps of HGN

Step 1: Lack of smooth pursuit

For all 3 steps, the officer will be checking each eye two times.

To check for lack of smooth pursuit, the officer moves the stimulus at a speed of two seconds from center position all the way to the other side. During this time, the officer is looking to see if the eye is able to pursue smoothly.


Step 2: Distinct and Sustained nystagmus at maximum deviation

To do this, the officer moves the stimulus all the way to the side, so that no white is left showing in the corner eye. The officer then must hold the stimulus there for at least 4 seconds (but not longer than 30 seconds as this can cause fatigue nystagmus). The reason the officer must hold it that long, is that people will show a nystagmus at maximum deviation, even when unimpaired up to a few seconds.


Step 3: Onset prior to 45 degrees

To do this, the officer is trying to see where a nystagmus is first present. The officer must move the stimulus at a rate that would take 4 seconds to wherever the officer is guessing 45 degrees is. Once the officer sees the nystagmus, he is to hold the stimulus there to see if it remains.

The HGN is usually inadmissible in Massachusetts.


Procedures for Walk-and-Turn Testing


1. Instructions Stage: Initial Positioning and Verbal Instructions

"Place your left foot on the line” (real or imaginary). Demonstrate.

"Place your right foot on the line ahead of the left foot, with heel of right foot against toe of left foot." Demonstrate.

"Place your arms down at your sides." Demonstrate.

"Maintain this position until I have completed the instructions. Do not start to walk until told to do so."

"Do you understand the instructions so far?" (Make sure suspect indicates understanding.)


2. Demonstrations and Instructions for the Walking Stage

Explain the test requirements, using the following verbal instructions, accompanied by demonstrations:

"When I tell you to start, take nine heel-to-toe steps, turn, and take nine heel-to-toe steps back." (Demonstrate 3 heel-to-toe steps.)

"When you turn, keep the front foot on the line, and turn by taking a series of small steps with the other foot, like this." (Demonstrate).

"While you are walking, keep your arms at your sides, watch your feet at all times, and count your steps out loud."

"Once you start walking, don't stop until you have completed the test."

"Do you understand the instructions?" (Make sure suspect understands.)

"Begin, and count your first step from the heel-to-toe position as 'One.'"



Walk and Turn Scoring

The officer is looking for the following 8 specific things (clues) in this test. If you do only 2 out of 8 wrong, the officer will decide you failed this test.


1. Cannot keep balance while listening to the instructions.

Record this clue if the suspect does not maintain the heel-to-toe position throughout the instructions. (Feet must actually break apart.) Do not record this clue if the suspect sways or uses the arms to balance but maintains the heel-to-toe position.

2. Starts before the instructions are finished.

3. Stops while walking. The suspect pauses for several seconds. Do not record this clue if the suspect is merely walking slowly.

4. Does not touch heel-to-toe. The suspect leaves a space of more than one-half inch between the heel and toe on any step.

5. Steps off the line. The suspect steps so that one foot is entirely off the line.

6. Uses arms to balance. The suspect raises one or both arms more than 6 inches from the sides in order to maintain balance.

7. Improper turn. The suspect removes the front foot from the line while turning. Also record this clue if the suspect has not followed directions as demonstrated, i.e., spins or pivots around.

8. Incorrect number of steps. Record this clue if the suspect takes more or fewer than nine steps in either direction.


Walk and Turn Test Conditions

“Walk-and-Turn test requires a designated straight line, and should be conducted on a reasonably dry, hard, level, nonslippery surface. There should be sufficient room for suspects to complete nine heel-to-toe steps”.


One Leg Stand

Procedures for One-Leg Stand Testing

Instructions Stage: Initial Positioning and Verbal Instructions

"Please stand with your feet together and your arms down at the sides, like this." (Demonstrate)

"Do not start to perform the test until I tell you to do so."

"Do you understand the instructions so far?" (Make sure suspect indicates understanding.)



Demonstrations and Instructions for the Balance and Counting Stage

Explain the test requirements, using the following verbal instructions, accompanied by demonstrations:

"When I tell you to start, raise one leg, either leg, with the foot approximately six inches off the ground, keeping your raised foot parallel to the ground.” (Demonstrate one leg stance.)

"You must keep both legs straight, arms at your side.”

"While holding that position, count out loud in the following manner: “one thousand and one, one thousand and two, one thousand and three, until told to stop.”

"Keep your arms at your sides at all times and keep watching the raised foot."

"Do you understand?" (Make sure suspect indicates understanding.)

"Go ahead and perform the test." (Officer should always time the 30 seconds. Test should be discontinued after 30 seconds.)


One Leg Stand Scoring

The officer is looking for the following 4 specific things in this test. If you do only 2 wrong the officer will decide you failed.

1. The suspect sways while balancing. This refers to side-to-side or back-and- forth motion while the suspect maintains the one-leg stand position.

2. Uses arms for balance. Suspect moves arms 6 or more inches from the side of the body in order to keep balance.

3. Hopping. Suspect is able to keep one foot off the ground, but resorts to hopping in order to maintain balance.

4. Puts foot down. The suspect is not able to maintain the one-leg stand position, putting the foot down one or more times during the 30-second count.


One Leg Stand Test Conditions

“One-Leg Stand requires a reasonably dry, hard, level, and non-slippery surface. Suspect's safety should be considered at all times.”

“The original research indicated that certain individuals over 65 years of age, back, leg or inner ear problems, or people who are overweight by 50 or more pounds had difficulty performing this test. Individuals wearing heels more than 2 inches high should be given the opportunity to remove their shoes”.

[1] Schultz v. State, 106 Md. App. 145 (1995)

Disclaimer: Past results do not guarantee a future outcome. Results include cases in both Massachusetts and New Hampshire. Attorney Dan Hynes is admitted to practice law only in Massachusetts and New Hampshire. This website may be considered advertising. Contacting us does not create an attorney/client relationship and the information on this site is not legal advice and may be inaccurate or not applicable to your case. Each case is different.

Mailing Address: Dan Hynes PO BOX 598 Merrimack, NH 03054